package com.example.yy.spinnertest_223yy;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {
    private TextView tvinfo;
    private Spinner spinner;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        init();
        //定义数据源----------1
        String[] cities = {"北京", "上海", "天津", "大连"};
        //实例化ArrayAdapter   定义适配器----2
        final ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, cities);//this上下文.条目布局.数据源
          //设置Spinner下拉按钮样式-----------3
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        //将spinner与ArrayAdapter绑定-------------4
        spinner.setAdapter(adapter);
        spinner.setPrompt("请选择城市");//本句为Spinner是对话框形式而设的标题
        //Spinner点击条目时间-----------5
        spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                tvinfo.setText("您选择的是："+parent.getItemAtPosition(position).toString());

            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {
                //不操作
            }
        });
    }

    private void init() {
        tvinfo=(TextView)findViewById(R.id.textView);
        spinner=(Spinner)findViewById(R.id.spinner);

    }
}
